5) Score the surface with a knife in an X pattern, turn heat to 425 degrees and bake for 30-40 minutes.

The advantage of the above method, is that you can do it all in one bowl that you keep progressively adding flour and water to. Other recipes say dump out half of the starter at each step, but I don’t think that’s necessary; just add more flour and water.

The vinegar lowers the pH so that yeast have an easier time growing, and undesirable bacteria stay out of the way.